IBM® Sametime® Community Server clusters provide redundancy, load balancing, and failover for community connections. Sametime Community Servers are clustered as part of an IBM Lotus® Domino® server cluster. A Sametime Community Server can belong to only one cluster.

IBM® Sametime® Community Server clusters provide redundancy, load balancing, and failover for community connections. Sametime Community Servers are clustered as part of an IBMLotus® Domino® server cluster. A Sametime Community Server can belong to only one cluster.

Setting up a cluster also allows users’ contact lists to be replicated to all servers in the cluster. Without a clustered Sametime environment, the VPUSERINFO database containing a user’s contact list is saved only on a user’s home server. If the home server is unavailable, the user cannot log in. If the user’s home server changes, the contact list is lost unless the user saved the list locally.

Six Domino servers is the maximum number of servers in a cluster, which means the number of Sametime servers in a cluster is also six. Generally, the largest communities can be supported with fewer than six Sametime Community Servers operating in a cluster. Two or more clusters pointing to the same Sametime Community Server is not supported.

This section explains how to cluster a group of Sametime Community servers, using the example of clustering two servers.